"PRE-SAFE Functions Limited See Owners Manual"
 

After owning 14 different Lexus and never had a single problem with any of them, I get the above message on my new ML350 BT this am on the way to work.:confused:

I have Googled it and there does not seem to be a specific fix but many others have had the same problem. Do not see how thew sensors are dirty but will check when the sun comes up. I also get a message while friving down the road that the "tire pressure monitoring system is unavailable"

I hope this is not the beginning of a maint horror!:eek:

Had two radar sensors in my rear bumper replaced today under warranty. Blind spot monitor started working intermitantly this winter and got a few Pre-Safe Functions limited too. They had to order the parts from Germany.

Had a nice C350 Coupe loaner for the day and cleaned any carbon buildup out of the engine for them... :)

Thanks for your reply.

I went out after it got light and wiped off all the bumper sensors and then looked for a sensor behind the grill. I really did not see anything that looked like a sensor so I am thinking that the sensor is just behind the windshield infront of the rear view mirror. All was also clean there.

When I got the above message it listed like three things that were no longer working of which I know two were the "distronic" feature and "blind spot" feature. I know the yellow LED indicators remained on at all times on the two side rear view mirrors regardless of my speed.

Anyway, when I started the ML all error messages were gone and all worked perfectly. Other than an occasional "Tire Pressure Monitoring System not working" messgae I have seen twice the ML is working without a flaw.

I will be taking it into service for a tire rotation and maybe oil change at 5K and will have them see if any error codes were recorded but from what I have read from Google searches, few if any were found.

Several Others have reported that the distronic radar system stops working when they drive by a cop with a radar gun and then it is back to normal after turning the car off and restarting, but I have not had this problem and not sure if your message is the same so hopefully they can help

The main distronic sensor is the MB star on the front grille. The short range sensors are behind the front bumper.

The parktronic sensors are the little circles on the front bumper.

I've had the Distronic drop out on long trips of over several hundred miles. It will recover if you acknowledge the fault and keep on driving with your right foot for another ten or so minutes. The first time this happened I just pulled over to the side of the road and restarted the car and it recovered that way. Since then I just let it recover by itself. On my last trip of 2100 miles it happened once and I just kept on driving and let it recover by itself. When it recovers you get the yellow message that 'Distronic is now availabe" again or like words. I've had similar problems on a XK Jaguar with its Adaptive Cruise Control and just live with it since it's a 'rare' event that only happens on long drives. I'm coming up on my 10K service and havn't decided whether or not to 'complain' about it since most 'fixes' will be guesses at the most probable 'bad actor' and not a accurate fix.

I do not think this was the case as I know where most of the cop like to hang out. But I will keep that in mind.

You know I saw a wire running into the back of the Star but it did not occur to me that it was actually a sensor.

Thanks for the info. I have not even used the cruise control, much less Distronic yet. I have not had the messages come back up so I am hoping it will be a every once in a while thing. I will mention it to service when I get my tire rotated in a few weeks.

Thanks everyone for all the information!

That black round surface behind the star is the sensor. Sort of a radome of sorts.

Good to know. I love the auto brake feature. It has beeped to warn me several times and if it only prevents one accident, it will be worth every dollar and more.

I had to turn off the lane assist as there were too many times it tried to correct my driving when I got too close to a solid or broken line. Might turn it back on for long highway work.

Overall I am loving the vehicle/truck!

The collision avoidance beeping has saved my bacon a few times but it also goes off a few times a week when not needed (quickly coming up behind someone who is turning off the road, etc). Even better is using the distronic cruise knowing you really can never rear end the car in front of you. I want to do a test and try to drive all the way to work never touching the gas or brakes.

The lane assist is pretty remarkable. Did a test recently on a deserted country road with a solid center line and solid line next to the shoulder. Had a buddy in the car and showed him this feature as we drove for a couple of minutes without touching the wheel, slowly going back and forth between the two lines but never going over. I was saying it would be a godsend to a dumb drunk driver as he would never go in the ditch! It does disengage the cruise control if activated which is smart.

Yep mine beeps several times a week to warn me that I am not applying the brake for the car turning just ahead of me. This lets me know it is working. I have not had it actually brake yet, just the beep warning. My M56 Infinity has the auto brake and it saved me big time! Once you see it work you do not forget!

As far as the lane departure thing, it worked very well but went off too often in city driving to suit me. Next time I am drunk:smash: I might give it a shot but for everyday driving, I am going to pass. The blind spot warning and auto brake are both used and well liked on my ML along with the radio which even beats my LX570 radio with ease.